In my personal opinion, I think if you're unsure where to ED2, it is best not to do it because having to commit to a school you're not 100% sure or could regret is really tough, and I definitely don't want you to go through that.
#need ED2 recommendations
mellow mango
In addition, since you are looking for a full ride, not doing ED could be helpful since you can compare financial aid packages through RD and have more time to decide which school is the best fit and most affordable for you.
Also, I went to Grinnell for a year, and I am happy to answer any questions about the school if you'd like!
And I hope this was helpful, best to you!